Patent · US Expired

Method of applying polarized film to liquid crystal display cells

US4181554A · kind A · utility

29Cited by
3References
10Claims
0Family size

Assignee

Inventor

Key dates

Filing dateOct 6, 1978
Grant dateJan 1, 1980
Priority date
Expiry dateOct 6, 1998

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10T156/1326
  • WIPO fieldOther special machines
  • WIPO sectorMechanical engineering

Abstract

In the disclosed method, a punch having a hollow open end is used to cut a portion of polarized film from a continuous sheet of polarized film. Subsequently, this portion of film is held by its perimeter while a piston that fits inside the punch and has a flexible convex shaped tip pushes the center of the portion of the held film against a liquid crystal display cell. Then the force exerted by the piston is increased. This forces the portion of film against the display cell with a rolling motion away from its center. The rolling motion eliminates the trapping of air bubbles between the portion of film and the display cell. By further increasing the force of the piston against the display cell, the flexible tip of the piston deforms in a lateral direction. Thus it completely covers the display cell, even though its undeformed cross-sectional area is less than that of the display cell.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.